Combination step and wall ladder



Dec. 12 1950 c. J. MIL LER COMBINATION STEP AND WALL LADDER 2Sheets-Sheet 1 Filed May 14, 1947 Ff 9 i3 5 A93 .33

INVENTOR Car/ J M/V/er ATTORNEY Dec. 12,, 1950 c. J. MILLER 2,533,391

COMBINATION STEP AND WALL LADDER Filed May 14, 1947 2 Sheets-Sheet 2 INVENTOR ATTORNEY Patented Dec. 12, 1950 UNITED STATES PATENT QFFlCE QQMBNAl QN STE ND ADDER Carl J Miller, Rochester, N. Y. A plication May 14,1947, serial No. 747,981 9 Claims. (Cl. eras-a3) The resent inventionrelates to a combination step and wall ladder and more particularly to astep ladder which may b'e'readily converted into a wall ladder or viceversa.

While step ladders and wall ladders are individually well known, eachtype of ladder has its limitations for use so that heretofore both kindsof ladders had to be kept on hand for the variety of requirementsarising 'in domestic and/or in d st a esta shments A'prirnary object ofthe present invention is the ro is n f a ombinat en t p] n sta lad r aable f u a a st ladde s a l ladd r a as y ang d rom one type o l dd tothe. the

Another objective of the invention is the provision of a ladder assemblycomprising two ladder member h nged to each other and an extension onone of said ladder members for eneasing the. o her la m mb r n e enbersare in s s tial alignm A further object is the provision of a ladder ambly h vin twdh s ladder m m extension on one oi said ladder members,and a latch means on the other of said ladder members for engaging saidextension and maintainin said members in substantial alignment;

Still another object of the invention is the provision of a ladderassembly having two hinged ladder membersf a brace member operativelyconnected therebetween, and a latch means on one. o aid, l dd r m mbe sd p m ttin disfconnection of said brace member from one of said laddermembers.

A still further object is the provision of a ladder assembly having twohinged ladder members, a brace member and an extension membertherebetween, and a pair oi latch means simultaneously operable torelease said brace member or said extension member for converting saidladder assembly from a step ladder to a wall ladder or vice versa. i

Other and further objects of the present in vention will be suggested tothose skilled in the art by the description which follows.

The aforementioned and other objects of the invention are embodied in aladder assembly comprising a front ladder member, a rear ladder memberhinged thereto, a brace member operatively connected between saidladdermembers,

tension and maintaining said ladder members in substantial alignment,and a manually operable means connected to botho'f saidlatch means foroperation to disengage the same and for nor mally urging both of saidlatch means to engaging" positions. The useful and operative arrangements and combinations of the above-mentioned elements are setforth in the appended claims.

Reference is hereby made to the accompanying drawings wherein likereference characters designate the same or similar elements and wherein:

Fig. l is a side elevation of the ladder assembly oithe invention as astep ladder.

Fig. 2 is a front elevation of my ladder assembly as a step ladder.

Fig. 3 is a side elevation of my ladder assembly in closed or foldedposition.

Fig. 4 is a side elevation of the ladder assembly of the invention withits halves in substantial alignment.

Fig. 5 is a fragmentary plan elevation of the central portion of 'myladder assembly as a wall ladder. i

Fig. 6 is fragmentary longitudinal cross-section through a side rail ofthe front ladder member showing the details of two latch means andmanually operable means therefor.

Fig. 7 is a fragmentary front elevation of a front ladder member withthe front wall of the side rail cut away.

Fig. 8 is a transverse cross-section taken on the line 3-3 of Fig. 1.

Fig. 9 is transverse cross-section through a modified formation of theside rail of'the 'front ladder member as though taken on the line 9-9 ofFig. 1.

Fig. 10 is a fragmentary perspective view of the abutment on the pailshelf.

In the illustrated embodiment of the invention,

the ladder assembly is essentially composed of a an extension on one orsaid ladder members engagi the. ot e lad member when s and a secondlatch means allowsdisconnection ofsai d brace 'means 'fro'm one of 'saidladder members. For convenience, a manually operable means is connectedto both of said latch means for simultaneous operation thereof and sa dlatch means and/or said manually operable m ans are biased by gravity orb other means normally to move both of said latch means to en ag ngpositions. Other s ecific advanta es and features of the ladder a semblvwill be pointed out in the detailed description to fo lo The frontladder member com rises in rather conventional fashion a air of siderails H] and H held in parallel s aced relation b a lura ity of steps 2.Preferably, said side rai s Ill and H are composed of sheet or tubularmetal such as aluminum, steel or other light and/or high strength metalor metal alloy. Also said side rai -s Ill and H are formed by knowntechnioues into a hollow section having arallel side walls I3 and I4 andhaving rounded front and rear edges H; and I6, such as shown in Figs. 8and 9. Other sections for the side rails it! and suitable for thenurnoses of the invention will be recognized by those skilled in theart.

The ste s l2 may also be formed from any suitable sheet metal andpreferablv have rolled front and rear edges I! and i8, the tread l9therebetween being deformed to strengthen the step l2 and to prevent sipping. Each ste l2 has at each end a projection 28 which extends intothe interior of the side rail for deformation. as

by riveting, against the inner face of side wall if? as shown for thelower step H! in Figs. 6 and '7 or which extends completely through theside rail for deformation, such as riveting, against the outer surfaceof side wall I4, see upper step I 2 in Fig. '7.

A top step member 2| is mounted at the top of said front ladder memberand is preferably provided with deformed or rolled edges including arear edge 22 which is provided with a pair of notches 23 and 24 for apurpose later to be described. At each end of top step member 2|, a pairof plates 25 and 26 have their top edges fastened to step member 2| asby flanging said edges of the plates 25 and 25 and bending thereover theend edge of said step member 2|. Said plates 25 and 26 are deformed soas to be complementary to and engage the side walls !3 and 4 of siderails Ill and H, see particularly Fig. 8, and a pair of rivets 2'!fasten said plates 25 and 26 to the tops of said side rails Ill and Asbest shown also in Fig. 8, said plates 25 and 26 are also cupped tostrengthen the sections for bearings 28 and 29.

A rear ladder member is composed also in rather conventional fashion ofa pair of side rails 30 and 3| held in parallel spaced relation by aplurality of rounds 32. As before the side rails 30 and 3| and rounds 32are composed of sheet or tubu ar metal or metal alloy having greatstrength and comparatively light weight. Preferably, said side rails 30and 3| have rounded or circular front and rear edges as illustrated andthe rounds 32 are hollow tubes extending through said side rails 30 andSI with the ends of said tubes spun over against the outer walls of said1'ails.30 and. 3

Said front and rear ladder members are pivotally connected to each otheras by a hinge connection now to be described. For such purpose, eachside rail 30 and 3| of the rear ladder member has its outer wallcircularly deformed inwardly to form a cup 33 and has its inner wallcircularly deformed inwardly to form a cup 33' which rests in thebearing 28 or 29. Bolts, such as bolt 34, extend through both of cups 33and 33' and through each cup bearing 28 and 29 for threaded or similarengagement by nuts 35 and 36, see Fig. 2. As a result, the front andrear ladder members are hinged together about an axis adjacent the upperends thereof and may be folded adjacent each other or swung intosubstantial alignment with each other.

An extension member is mounted on one of said ladder members and engagesthe other ladder member when both ladder members are in substantialalignment. Such an extension member may be composed of a single side armex tending from one of the side rails of said one ladder member, a pairof side arms extending from both of the side rails of a ladder member,or may include a cross-bar between a pair of side arms. Side arms 3i and3B are illustrated as being integral with and extending from side rails36 and 3| but it is obvious said side arms 3'! and 38 may be supplied asan attachment for connection to the side rails 36 and 3! in any suitablemanner. Said side arms Bl and 38 are each formed so as to permitmovement of the ladder members into alignment as by outward lateralofisets 39 and 4D. A cross-bar 4! extends between side arms 3'! and 38to provide rigidity to the extension member and to constitute lateralinward off-set portions for engaging the other ladder member. Saidcross-bar 4!' may be covered with a tube 42 of rubber or like material.

The front edges of the side rails ID and H are each respectivelyprovided with notches 43 and 44 which are located to receive theextension member and more particularly the cross-bar 4| when the laddermembers are moved into substantial alignment, see Fig. 4. In thisposition, the ladder assembly can be used as a wall ladder or in placeof an extension ladder.

In order to maintain the ladder members in their position of substantialalignment, a latch means is provided to engage and hold said extensionmember. Most conveniently and for greatest effectiveness such latchmeans is provided adjacent one or both of notches 43 and 44 in the siderails Ill and II. Such a latch means preferably comprises a latch plate45 pivotally mounted on a pin 46 riveted to the inner face of side wallM of side rail ill and having a nose portion 45' and a locking tongue 41with a strike face 48. Said strike face has a fiat portion for closingthe end of notch 43 and/or notch 44 and a sli ht inward radius near theend of the face will improve the automatic operation of the latch meanslater to be described. The locking tongue 41 on latch plate 45 biasesthe same by gravity in a counterclockwise direction in Fig. 6 but suchbias may be obtained by other means if desired. The latch plate 45 ispivoted and arranged such that engagement of said strike face 48 thereofby the cross-bar 4| will rotate said latch plate 45 in a clockwisedirection and permit said crossbar 45' to enter into and be seated innotch 43 whereupon the gravity bias on the latch plate 45 returns it tothe position shown and locking tongue 4'! engages and holds saidcross-bar 4| within notch 33. A similar latch means for engaging thecross-bar 4| may be placed within side rail l adjacent notch 44 also tohold said cross-bar 4| therein. At the same time, side rails 3B and 3|of the rear ladder member are within and engaging the notches 23 and 24in the rear edge of .top step member 2| so that the two ladder membersarerigidly and securely held and positioned with respect to each otherand any rela tive lateral movement therebetween is substantially:eliminated.

As seen clearly from Fig. 1 the side rails 30 and 3! of the rear laddermember each have an angular bend 30' adjacent the hinge connection andthe side arms 3'! and 38 each have a similar but reverse bend, such asbend 31, adjacent the hinge connection. Such angular bends have twoadvantages, first the bends such as 538 in the side rails 30 and 3!permit a compact relationship thereof to the side rails I6 and l i infolded position of the ladder members and secondly the effect of twobends is combined to allow the two ladder members to assume more nearlya position of direct alignment in extended position of the laddermembers.

When the ladder assembly of the invention is to be used as a stepladder, the two ladder members are moved to the position shown in Fig. 1and a brace member in the form of a pail shelf is operatively connectedtherebetween. Such pail shelf comprises a pair of side arms 49 and 59held in parallel spaced relation by a pair of cross-straps 5i and 52forming the platform of the pail shelf, a cross-bar 53 extending betweenthe opposite ends of arms 49 and 52 and a tube 54 fastened at each endto the center portions of arms 49 and 5.6. A tie bolt 55 extends betweenside rails 30 and 3! and through said tube 54 so that the pail shelf isfree to rotate between said rails 30 and Si. Said cross-bar 53 is longerthan the normal spacing between the inner and opposed walls of the siderails It) and i i of the front ladder member and between the inner andopposed walls of side rails 39 and ti of the rear ladder member. Saidpail shelf is balanced so as to swing normally into a vertical positionwith the end carrying straps 5i and 52 lowermost.

Such vertical position of the pail shelf will cause it to assume a moreconvenient or out-ofthe-way position when the ladder members are in theextended position shown in Fig. 4 because the cross-straps 5! and 52 areon the far side of side arms 49 and 5B and there is minimum interferencewith a person standing on top step 2! or stepping on tube 54 or theround 32 just above it. An abutment and fastening means is providedbetween the pail shelf and one or both of the side rails of the rearladder member. Such abutment and fastening means is preferably arrangedto engage the side rail when the pail shelf is swung to a positionadjacent the side rails 3i] and 3E and yet readily releasable andpermitting movement of the pail shelf in a clockwise direction from itsposition of engagement. Such an abutment and fastening means may besupplied in any of several ways and conveniently coin,- prises a stirrupmember 56 fastened to either or both of cross-straps 5i and 52preferably by means of the rivets 5! which also fasten crossstrap 52 tothe side arms t9 and 5! Said stirrup member 55 is preferably in the formof a U- shaped leaf spring and is located and formed so that the bottomcurved surface thereof engages the rounded surface of the rear edge ofside rails 3t and 3! of the rear ladder member just prior to theabutment of the ends of cross-bar 53 against the front edges of siderails to and St at which time the end of member 56 frictionally engagesthe faces of side rails 36 and 3!.

When the ladder assembly is swung open and the ladder members are insubstantial alignment, the heavier end carrying the cross-straps 5| and52 of the pail shelf swings downwardly and a slight pressure thereonwill cause engagement of stirrup, members 5t with the, faces of siderails 30 and 31 which will eliminate excessive swinging movement of thepail shelf. Such resilient clamping is only sufficient to overcome thegravitational tendency of the pail shelf when the ladder members arefolded and the cross-bar 53 is held slightly away from the front edgesof side rails 36 and 3| for re-entry into recesses 59 in the rails Itand l I of the front ladder member.

The cross-bar 53 of the pail shelf is arranged for operative engagementwith the front ladder member as by being longer than the spacing betweenthe inner walls, one of which is side wall It, of the side rails l8 andII. Said inner walls of side rails it and II are both provided with anelongated recess 59 see Figs. 1 and 6. Said recess 59 has an open end 69located at the rear edge of one or both of side rails ID and I! andlocated for entry of the ends of cross-bar 53 when the ladder membersare in the closed or folded position thereof. Said elongated recess 59has a closed end 6! located at a position to limit the opening orunfolding movement of the ladder members to an extent to give goodstability to the ladder assembly when used as a step ladder asillustrated in Fig. 1.

The elongated recess 59 may also be provided as deformed or depressedtrack 52 in the inner, facing walls of the side rails in and H. Such atrack 52 is shown in Fig. 9 and is arranged so that the walls thereofform the elongated recess 59 with an open end and a closed end. Also theengaging ends of the cross-bar 53 may be provided with rollers 53mounted in each end thereof, see Fig. 9, and may be individually mountedon the ends of side arms t9 and 59.

A latch means is preferably located adjacent the lower end {iii of theelongated recess 59 so that the brace means is normally held withinelongated recess 59. Such a latch means comprises a latch plate 56pivotally mounted on the side rail It by a pin 65, has a locking tongue66 normally closing said recess 59, and has a nose portion 51 forengaging a part of the side rail is and limit the rotation of said latchplate 55. A strike surface 58 is provided along the outer edge oflocking tongue 66 and is shaped so that engagement by the ends ofcross-bar 53 will swing latch plate 64 out of the path of the elongatedrocess 59 to permit entry of said cross-bar 5-3 thereinto. Also thelatch plate 6d arranged and balanced so that the normal position is thatshown in Fig. 6.

Although both latch mean are automatically displaced for entryrespectively of cross-bar 4! into notches G3 and #34 and the ends ofcrossbar 53 into the elongated recesses 59, it is necessary to providemanually operable means for retracting said latch means and, if desired,for further biasing said latch means normally to look,- ing position.The manually operable means may be provided in any Way so as toaccomplish the aforementioned purposes and may comprise a connecting rodpivotally connected at one end to the latch plate by a pin it and at itsother end to the latch plate it by a pin H, hand bar 1 2 having off-setends it and i extending through and journaled in the inner and facingwalls of the side rails and il, a disc fastened on the ends, such asoff-set end '13, of handbar 12 within side rail iii, and a secondconnecting rod '16 pivotally connected at one end eccentrically to disc'55 by a pin ii and at the other end to pin H on latch member 6 1.Spares tion of hand bar 12 in a clockwise direction as seen from Fig. 6will rotate said disc and latch bar '12 thereof are arranged so as toaugment the biasing of the two latch means to locking positions but yet'not sufficient to prevent the automatic and momentary opening of thelatch means respectively by the cross-bars 4| or 53.

Feet 18 composed of rubber or other suitable material may be fitted ontothe lower ends of the side rails in, I 39 and 3! to improve the tractionof said ends with the floor, wall or other surface.

The operation of the ladder assembly of the invention will now bedescribed and is as follows: The ladder assembly is normally stored withthe ladder members in closed or fully folded position as shown in Fig.3. Preferably, the brace member remains operatively connected to theother ladder member with the ends of crossbar 53 within the elongatedrecesses 59 and maintained therein by the latch means including latchplate 84 which is biased to locking position.

The ladder assembly may be used as a step ladder in the regular way byspreading the front and rear ladder members to he extent permitted bythe brace means whereupon the pail shelf is swung into horizontalposition in the usual fash ion. In this position the cross-bar 4: of thee::- tension member is above the top step member and provides a usefuladdition to the step ladder, said cross-bar 4| being capable of servingas a hand rail for a person climbing the step ladder and also assteadying support against the shins of a person standing on said topstep member 2!.

An important and unusual feature of the ladder assembly of the inventionis its capability to be converted into a wall ladder. With the laddermembers in the closed position shown in Fig. 3, the hand bar 12 of themanually operable means is swung forwardly and upwardly toward the step|2 just above it and in turn the disc l5 and connecting rod 16 areoperated to rotate latch plate 64 in a clockwise direction as seen fromFig. 6 and the locking tongue 66 is withdrawn from its normal positionacross elongated recess 59. The ends of cross-bar 53 ma now be swung outof said recesses 59 by rotating the pail shelf in a counterclockwisedirection as viewed from Fig. 3 and/or by rotating the rear laddersection in the same direction. The rear ladder member can now be swungabout its hinge connections into a position of substantial alignmentwith the front ladder member. At the same time, the cross-bar 4| of theextension member enters notches 43 and 44 in the front edges of the siderails Hi and I! and the edges of side rails 36 and 3| enter and engagethe notches 23 and 24 in the rear edge of the top step member 2 Fourpoints of engagement are thus provided between the two ladder members toinsure ample rigidity therebetween and the weight of a person using theladder against a vertical wall or other surface increases the pressureon said four points of engagement.

Although the ladder assembly with its members in substantial alignmentis self-locking in one direction under conditions of normal use, theextended ladder assembly can be more readily manipulated or shifted whenthe members are locked in aligned position. Such locking can beaccomplished by manual opening of the latch means and latch plate 45 bythe hand-bar l2 and manual closing by reverse movement thereof after thecross-bar 4| has entered notches 43 and 44 in the front edges of siderails l0 and H. However, the opening and closing of the latch means forcross-bar 4| is also automatic. Said latch means including latch plate45 is normally in the position shown in Fig. 6. As the rear laddermember is swung into substantial alignment with the other ladder memberthe cross-bar 4| enters slots 43 and 44 and abuts against the strikesurface 48 including the inward radius thereon and the pivotal axis ofsaid latch plate 45 are such that further movement of cross-bar 4|swings the latch plate 45 in a clockwise direction until locking tongue4'! opens the remainder of slots 43 and 44 and cross-bar 4| abuts thebottoms thereof and latch plate 45 returns to its normal position withlocking tongue 41 engaging and holding the cross-bar 4| within saidslots 43 and 44. In this manner automatic unlocking and locking of thelatch means for cross-bar 4| has been accomplished.

When it is desired to convert the ladder assembly to a step ladder orfold the ladder members for storage, the hand bar 12 is swung toward thesuperjacent step 52 to retract the locking tongue 4! and permit theswinging of the ladder members to the closed position as shown in Fig.3. If it is desired to connect the brace means to the front laddermember, said hand bar '12 may be held in unlocking position and the endsof cross-bar 53 introduced into elongated recesses 59. But it is notnecessary manually to hold the latch means including latch plate 64 inopen position because that latch means can be automatically opened bythe ends of cross-bar 53 in a manner that is quite obvious and verysimilar to that in which crossbar 4| automatically operates the otherlatch means.

The latch means for cross-bars 4| and 53 may be provided singly or inpairs and may, if desired, be independent of each other and of the otherhalf when provided in pairs. The illustrated embodiment shows andcontemplates both latch means provided in pairs and all simultaneouslyoperated but it is well within the scope of the disclosure and of theinvention that such latch means can be individually and singly providedand operated.

Many variations of the ladder assembly shown are possible withoutdeparting from the spirit of the invention, the scope of which isdefined in the appended claims.

Having now particularly described my invention what I desire to secureby Letters Patent of the United States and what I claim is:

1. A ladder assembly comprising a front ladder member having side railsin parallel spaced relation and a step member over the tops of said siderails, a rear ladder member having side rails in parallel spacedrelation and hinged at one end to said step member, and an extensionmember having side arms extending from each side rail of said rearladder member and each laterally and outwardly off-set, and having across-bar between said side arms and above said step member in foldedand adjacent positions of said ladder members, the side rails of thefirstmentioned ladder member each being provided with a recess toreceive said cross-bar and the rear edge of said step member beingprovided with notches spaced to receive the respective side rails of therear ladder member when said ladder members are unfolded intosubstantial alignment.

2. A ladder assembly comprising a front ladder member having hollow siderails in parallel spaced relation, a rear ladder member having siderails in parallel spaced relation and hinged at one end to said frontladder member, an extension member having side arms extending from eachside rail of said rear ladder member and having a cross bar between saidsidearms and above the tops of said ladder members in folded andadjacent positions thereof, the side rails of said front ladder membereach being provided with recesses to receive said cross bar when saidladder members are unfolded into substantial alignment, a latch meanswithin each hollow side rail of the front ladder member and having aportion to engage and hold said cross-bar within said recesses.

3. A ladder assembly comprising one ladder member having side rails inparallel spaced relation and with inner opposed and parallel faces, asecond ladder member hinged at one end to the upper end of said oneladder member, and a brace member pivotally mounted upon said secondladder member and having a cross bar at one end thereof parallel to thepivotal axis of said brace member and longer than the space between theopposed faces of said side rails, at least one of said inner faces beingprovided with an elongated recess, one end thereof being open andlocated to permit connection and disconnection of the end of saidcross-bar in closed position of said ladder members, and the other endof said recess being closed to abut the end of said cross-bar to limitthe opening movement of said ladder members.

4. A ladder assembly comprising one ladder member having hollow siderails in parallel. spaced relation and with inner and opposed walls, asecond ladder member hinged at one end to the upper end of said oneladder member, and a brace member pivotally mounted upon said secondladder member and having a cross-bar at one end thereof and longer thanthe space between said inner walls, at least one of said inner wallsbeing deformed inwardly to provide an elongated recess for receiving theend of said cross-bar, one end thereof being open and located to permitconnection and disconnection of the end of said crossbar in closedposition of said ladder members, and the other end of said recess beingclosed to abut said end of the cross-bar to limit the opening movementof said ladder members.

5. A ladder assembly comprising one ladder member having hollow siderails in parallel spaced relation and with inner and opposed Walls, asecond ladder member hinged at one end to the upper end Of said oneladder member, a brace member pivotally mounted upon said second laddermember and having a cross-bar at one end thereof and longer than thespace between said inner walls, at least one of said inner walls beingdeformed inwardly to provide an elongated recess for receiving the endof said cross-bar, one end thereof being open and located to permitconnection and disconnection of the end of said crossbar in closedposition of said ladder members, and

the other end of said recess being closed to abut said end of thecross-bar to limit the opening movement of said ladder members, and alatch means within at least one of said hollow side rails and having aportion normally closing the open Qatar '10 end of said elongated recessand manually operable to open said latch means for disengaging saidcross-bar from said recess. 6. A ladder assembly comprising a frontladder member having hollow side rails in parallel spaced relation andwith inner and opposed walls, a rear ladder member having side rails inparallel spaced relation and hinged at one end to the upper end of saidfront ladder member, an extension member having side arms extending fromeach side rail of said rear ladder and having a cross-bar between saidside arms, the front edges ofsaid side rails each being provided with arecess to receive the cross-bar of said extension member when saidladder members are in substantial alignment, a brace member pivotallymounted upon said second ladder member and having a cross-piece longerthan the space between said inner walls which are deformed inwardly toprovide in each an elongated recess for receiving the respective ends ofsaid cross-piece, one end of each recess being open and located toreceivev the ends of said cross-piece in closed position of said laddermembers, a latch means within each hollow side rail and having a portionmovable to close the recesses in the front edges of said side rails, anda second latch means within each hollow side rail and having a portionnormally closing the open end of said elongated recess and movable toopen said end thereof.

'7. A ladder assembly comprising a front ladder member, a rear laddermember, a hinge connection between the ends of said members, a bracemember operatively connected between said members for limiting theangular displacement thereof, a latch means on one of said members andoperative to permit disconnecting said brace member from one of saidladder members, an extension on one of said ladder members, extendingbeyond said hinge connection in folded and adjacent positions of saidmembers, and engaging the other ladder member when said members are s"ong into substantial alignment, a second latch means between saidextension and said other ladder member and for maintaining said laddermembers in a position of substantial alignment, and a manually operablemeans connected to both of said latch means and for simultaneous move--ment thereof to disengaging position.

8. A. ladder assembly comprising a front ladder member having hollowside rails in parallel spaced relation and with inner and opposed walls,a rear ladder member having side rails in parallel spaced relation andhinged at one end to the upper end of said front ladder member, anextension member having side arms extending from each side rail of saidrear ladder and having a cross-bar between said side arms, the frontedges of said side rails each being pro vided with a recess to receivethe cross-bar of said extension member when said ladder members are insubstantial alignment, a brace member pivotally mounted upon said secondladder member and having a cross-piece longer than the space betweensaid inner walls which are deformed inwardly to provide in each anelongated recess for receiving the respective ends of said cross-piece,one end of each recess being open and located to receive the ends ofsaid crosspiece in closed position of said ladder members, a latch meanswithin each hollow side rail and having a portion movable to close therecesses in the front edges of said side rails, a second latch meanswithin each hollow side rail and having a portion normally closing theopen end 11 of said elongated recess and movable to open said endthereof, and a manually operable means connected to both of said latchmeans within both of said side rails for simultaneously opening andclosing of each.

9. A ladder assembly comprising a front ladder member having hollow siderails in parallel spaced relation and with inner and opposed walls, arear ladder member having side rails in parallel spaced relation andhinged at one end to the upper end of said front ladder member, anextension member having side arms extending from each side rail of saidrear ladder and having a cross-bar between said side arms, the frontedges of said side rails each being provided with a recess to receivethe cross-bar of said extension member when said ladder members are insubstantial alignment, a brace member pivotally mounted upon said secondladder member and having a cross-piece longer than the space betweensaid inner walls which are deformed inwardly to provide in each anelongated recess for receiving the respective ends of said cross-piece,one end of each recess being open and located to receive the ends ofsaid crosspiece in closed position of said ladder members, a latch meanswithin each hollow side rail and having a portion movable to close therecesses in the front edges of said side rails, a second latch meanswithin each hollow side rail and having 12 a portion normally closingthe open end of said elongated recess and movable to open said endthereof, and a manually operable means connected to both of said latchmeans within both of said side rails for simultaneously opening andclosing of each, said manually operable means being arranged, when saidfront ladder member is upright, so that gravity causes movement of saidlatch means to closed positions.

CARL J. MILLER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 288,883 Spencer Nov. 20, 1883603,848 Herder May 10, 1898 672,945 Kloepfer Apr. 30, 1901 1,010,832Welden Dec. 5, 1911 1,066,680 Swart July 8, 1918 1,228,248 Rudd May 29,191? 1,829,346 Frommeyer Oct. 27, 1931 2,313,469 Forsman Mar. 9, 1943FOREIGN PATENTS Number Country Date 516,711 Germany Jan. 27, 1931

